drm/amd/display: Check denominator crb_pipes before used

commit ea79068d4073bf303f8203f2625af7d9185a1bc6 upstream.

[WHAT & HOW]
A denominator cannot be 0, and is checked before used.

This fixes 2 DIVIDE_BY_ZERO issues reported by Coverity.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Cliff Liu <donghua.liu@windriver.com>
Signed-off-by: He Zhe <Zhe.He@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c b/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
index e78954514e3e24ddff9bb43d6c76eb3111f2b60e..958170fbfece7dc1ab6152d77c278f2ba46a6035 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn315/dcn315_resource.c
@@ -1772,7 +1772,7 @@ static int dcn315_populate_dml_pipes_from_context(
                                bool split_required = pipe->stream->timing.pix_clk_100hz >= dcn_get_max_non_odm_pix_rate_100hz(&dc->dml.soc)
                                                || (pipe->plane_state && pipe->plane_state->src_rect.width > 5120);
 
-                               if (remaining_det_segs > MIN_RESERVED_DET_SEGS)
+                               if (remaining_det_segs > MIN_RESERVED_DET_SEGS && crb_pipes != 0)
                                        pipes[pipe_cnt].pipe.src.det_size_override += (remaining_det_segs - MIN_RESERVED_DET_SEGS) / crb_pipes +
                                                        (crb_idx < (remaining_det_segs - MIN_RESERVED_DET_SEGS) % crb_pipes ? 1 : 0);
                                if (pipes[pipe_cnt].pipe.src.det_size_override > 2 * DCN3_15_MAX_DET_SEGS) {